Labour has offered to consider supporting Resource Management Act reforms aimed at speeding up the building of new homes, but says the bill would need to be split first.

The comments come after Prime Minister John Key said yesterday that the Government's coalition partners had successfully halted plans to overhaul planning laws. He also accused Labour of failing to support any of the Government's moves to address housing affordability.

The Maori Party and United Future MP Peter Dunne teamed up to oppose reforms of the act, saying the reforms placed economic growth ahead of environmental protection.

National needed either party's vote to get the legislation over the line.

National wants to cut the cost of building and argues the present consenting processes take too long and are costly, slowing developments.

Environment Minister Amy Adams has spearheaded the bill and also wants to shake up part two of the RMA, which puts environmental safeguards in place.

Key yesterday confirmed negotiations have stalled and he has "parked up" the reforms until after September's general election.

"I think it is very unlikely we will introduce the RMA bill before the election,' he said.

"I think we will campaign on what we want to do and see what the makeup looks like, whether we are the Government after the election ... I've decided to park it up."

Key has also accused Labour of failing to support government measures to boost the supply of housing.

Cunliffe today moved to nix that criticism by offering to work with National on the RMA reforms.

Cunliffe suggested the bill could be split into two parts.

Labour was willing to negotiate with the Government on the measures to improve housing affordability, but not those which he said undermined the core principles of the bill.

"We're willing to assist, if the text is reasonable, to speed up measures on housing affordability and potentially offer bipartisan support on that part of the bill," Cunliffe said.

He denied the move was a stunt aimed at curbing criticism that Labour had tried to block National's housing affordability measures.

"We think because the printer left the housing chapter out of the Budget that it would be really good to put the gas pedal on measures that would improve housing affordability for New Zealanders and we'd like to offer support for that depending on the context," Cunliffe said.

"I make the offer in good faith and I hope the prime minister will look seriously at it."

However, Adams said earlier the Government would keep the bill as it was, and campaign on it at the election.

"We want to see an RMA that focuses on both protecting the environment and making sure that other needs of communities are met including having enough land to build houses and making sure jobs are created," she said.

"Those are the changes that we want to put into the section that's of the most contention.

"And yet the parties who say they care about those things aren't prepared to back, so look, we'll take it to the election and we'll see where we go from there."

Adams refused to split the bill so government support partners could vote on "the bits they like, and not on the bits they don't".

"If you want different outcomes you've got to be prepared to do things differently, and we know at the moment that we're not getting enough land made available for housing, we're not getting enough new jobs and businesses being created in some of our regions.

"A big part of that often, is down to the way the RMA works," she said.

The RMA was there to both protect the environment and provide for the needs of all of the community, she said.